This research seeks to quantify the physiologic aspects of sexual health in men and women. Conventional equipment records heart rate, blood pressure, skin conductance, respiratory ventilation, and concentrations of O2 and CO2 in expired air. Special custom-designed instruments measure pelvic blood volume, blood volume pulse, and muscle contractions. These variables are recorded and stored in digitized form by computer during genital self-stimulation and coitus. Computer analysis can then examine the multiple variables for patterns of change during the sexual response, and describe the within-subject and between-subject variability. Comparison is made between men and women, and among four different sexual activities. In addition to physiologic data, subjective ratings are obtained before and after each recorded session. Perceived levels of sexual arousal, orgasmic intensity, duration, and satisfaction are compared with the levels of physiologic change in the numerous variables. This comparison will determine the extent of correlation between perception of pleasure and objective response.